THERMAL-DECOMPOSITION OF FLUORINATED DIOXOLANE CARBOXYLATES

Synthesis of fluorodioxole olefin monomers by thermal decomposition of fluorinated dioxolane carboxylic acid and the corresponding acyl chlo ride was explored. Complex product formation is observed, including ac yl fluoride from Cl-F exchange, the hydro-dioxolane from proton abstra ction, the cyclic ether ketone from dioxolane ring opening, and the ep oxy acid fluoride from thermal rearrangement. The product distribution is strongly dependent upon reaction conditions. The main influential factors include the reaction temperature, the base used for the reacti on, the presence or absence of solvent, and the counter ion associated with the intermediate salt. A mechanism is proposed to rationalize bo th the results and the product distribution. Methods to make authentic samples for product analysis are reported.